I'm also redoing my kitchen and planning for concrete support for under mount sink. and wooden cabinet besides it... I had under mount sink with wooden cabinets... after 10 years of usage... water seepage starts under and the wooden support no longer can support... the sink came out a little loose.. I was considering top mount next.. but top mount is usually sealed with silicon around it.. long run the silicon will also wear off and worst turn mouldy and unsightly since water cannot sweep into the sink as easily as under mount.. the next solution is to build concrete support for under mount sink as my ID suggested. cant show any picture how it would look like yet as I'm pending ID drawings...